{ "id": "1511.07268", "version": "v1", "published": "2015-11-23T15:21:44.000Z", "updated": "2015-11-23T15:21:44.000Z", "title": "Automorphism groups of Cayley graphs generated by block transpositions and regular Cayley maps", "authors": [ "Annachiara Korchmaros", "István Kovács" ], "categories": [ "math.CO", "math.GR" ], "abstract": "This paper deals with the Cayley graph $\\mathrm{Cay}(\\mathrm{Sym}_n,T_n),$ where the generating set consists of all block transpositions. A motivation for the study of these particular Cayley graphs comes from current research in Bioinformatics. As the main result, we prove that Aut$(\\mathrm{Cay}(\\mathrm{Sym}_n,T_n))$ is the product of the left translation group by a dihedral group $\\mathsf{D}_{n+1}$ of order $2(n+1)$. The proof uses several properties of the subgraph $\\Gamma$ of $\\mathrm{Cay}(\\mathrm{Sym}_n,T_n)$ induced by the set $T_n$. In particular, $\\Gamma$ is a $2(n-2)$-regular graph whose automorphism group is $\\mathsf{D}_{n+1},$ $\\Gamma$ has as many as $n+1$ maximal cliques of size $2,$ and its subgraph $\\Gamma(V)$ whose vertices are those in these cliques is a $3$-regular, Hamiltonian, and vertex-transitive graph. A relation of the unique cyclic subgroup of $\\mathsf{D}_{n+1}$ of order $n+1$ with regular Cayley maps on $\\mathrm{Sym}_n$ is also discussed. It is shown that the product of the left translation group by the latter group can be obtained as the automorphism group of a non-$t$-balanced regular Cayley map on $\\mathrm{Sym}_n$.", "revisions": [ { "version": "v1", "updated": "2015-11-23T15:21:44.000Z" } ], "analyses": { "keywords": [ "automorphism group", "block transpositions", "left translation group", "balanced regular cayley map", "cayley graphs comes" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }